Nonfunctional overreaching leads to inflammation and myostatin upregulation in Swiss mice.

• Grant number: 13/14172-8
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: August 01, 2013
• End date: January 31, 2014
• Field of knowledge: Health Sciences - Physical Education
• Principal Investigator: Adelino Sanchez Ramos da Silva
• Grantee: Adelino Sanchez Ramos da Silva
• Host Institution: Escola de Educação Física e Esporte de Ribeirão Preto (EEFERP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The aims of the this study were a) to verify whether the performance decrease induced by nonfunctional overreaching (NFOR) is linked to high concentrations of cytokines in serum, skeletal muscles, and liver; b) to verify muscle myostatin adaptation to NFOR; c) to verify the effects of chronic glucose supplementation on the parameters mentioned above. Mice were divided into control (C), trained (TR), overtrained (OTR) and supplemented overtrained (OTR+S). The incremental load test (ILT) and exhaustive test (ET) were used to measure performances before and after exercise protocols. 24h after ET, muscles and liver were removed and stored at -80oC for subsequent measurements. Total blood was collected from decapitation for subsequent determination of cytokine concentrations. Generally, OTR and OTR+S presented higher contents of IL-6, TNF-alpha, GLUT-4 and myostatin in muscle samples compared to C and TR. Glucose supplementation attenuated the high contents of IL-6, TNF-alpha and IL-15 in liver, and of IL-6 in serum. In summary, NFOR led to low-grade chronic inflammation and myostatin upregulation. (AU)